A test gives 45 true positives, 10 false positives, 5 false negatives and 40 true negatives. What is its specificity?
Answer and explanation
Correct answer: D. 80%
- Step 1: Specificity = TN / (TN + FP) = 40 / 50.
- Step 2: This equals 80%.
Answer
80%.
Why not the others: The other percentages are the other test characteristics (sensitivity, specificity, positive and negative predictive value), which use different denominators.
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